1. Field of the Invention
This invention relates to devices or equipment for changing sharp blades such as the elongate, sharp blades of ice resurfacing machines.
2. Prior Art
Modern ice resurfacing machines, such as the machines sold by Frank J. Zamboni and Co. Inc. under the trade-mark ZAMBONI™, have been used in arenas both in Canada and the United States for many years. These machines employ a large, elongate steel blade that is mounted under the machine. The blade has a very sharp leading edge to scrape the ice surface. This sharp edge will become dull over time at which point the blade must be sharpened. Since sharpening involves removing material from the cutting edge, the width of the blade is reduced each time the blade is sharpened. Therefore, the blade will eventually have to be replaced following many instances of sharpening.
To lengthen the life of the blade, the blade is provided with two rows of threaded sockets. The holes of each of the rows of threaded sockets are disposed for alignment with holes of the blade receiver of an ice resurfacing machine for which the blade is intended to be mounted. The trailing row of threaded sockets, i.e. the row that is furthest from the cutting edge, is used when the blade has a width of less than 4″, while the leading row of threaded sockets, i.e. the row closest to the cutting edge, is used when the blade has a width of 4-5″.
Procedures for changing blades vary. One conventional procedure is to use a set of blocks. To install a sharp blade, the blade receiver of an ice resurfacing machine is raised and blocks are placed underneath the receiver. The sharp blade is removed from its sheath and placed on the blocks. The blade receiver is then lowered until it comes into contact with the blade. The position of the blade is then adjusted until the mounting holes of the blade align with the mounting holes of the blade receiver. Once aligned, the blade is secured to the receiver using a bolt and nut arrangement.
To remove a dull blade, the operation is performed in reverse. Of course, when removing a dull blade, no positioning of the blade is necessary. Another conventional procedure is to use a jack in a similar fashion. However, instead of lowering the blade receiver to a blade resting on the jack, the jack lifts a blade resting thereon to the blade receiver.
It will be appreciated that conventional procedures for changing blades are less than ideal. The risk that the blade will fall from the set of blocks or the lift jack, as the case may be, is considerable. Moreover, during installation of the sharpened blade, accurately positioning the blade under the blade receiver such that the threaded sockets align with the holes of the blade receiver can be difficult. Further, the described procedures are recommended to be performed with at least two persons and, even then, can take upwards of 45 minutes. Accordingly, changing the blade of an ice resurfacing machine not only presents certain risks to the handler or installer, but can be labour intensive and time consuming.